Juan F. Jiménez

Genetic variations and migration pathway of Juniperus thurifera L. (Cupressaceae) in the western Mediterranean region

Random amplified polymorphic DNA (RAPD) analysis and length variations in the chloroplast trnL-trnF intergenic spacer were used to analyze the geographic structure of Juniperus thurifera L. populations in Spain and North Africa. The chloroplast DNA analysis indicated three size classes of the spacer, but was uninformative of any geographic pattern. In contrast, the RAPD data based on 127 polymorphous bands clearly showed the existence of three population groups: (a) a group comprising two populations from northeastern Spain and two from southern Spain, (b) a group comprising the rest of the Spanish populations, and (c) a group which consisted of the two Moroccan populations. Analysis of molecular variance (AMOVA) showed that 24% of the variation is found between groups of populations, 15% between populations within groups, and 61% within populations. The results are consistent with a hypothetical migration of J. thurifera starting from central Europe, passing through France and Spain, and finally reaching...

Isolated populations or isolated taxa? A case study in narrowly-distributed snapdragons (Antirrhinum sect. Sempervirentia) using RAPD markers

RAPD fingerprinting was used to study species boundaries in narrowly distributed endemic species in Antirrhinum section Sempervirentia. Based on RAPD data, similarity values within species were relatively high but pair-wise similarity values among species were low. Partitioning of the overall RAPD variation using AMOVA showed that most of the variation was found among species (58.06%), whereas the remaining phenotypic diversity was distributed among populations (25.18%) and among individuals within populations (16.76%). Comparison of the matrices of geographical distances and phenetic distances (1-Dice index) among populations using the Mantel test showed a moderate, but statistically significant correlation (r=0.588, P < 0.01), suggesting that isolation by distance is responsible for the distribution of genetic variation among Antirrhinum populations. Phenetic relationships among Antirrhinum samples based on a Dice similarity matrix showed a clear taxonomic pattern, confirming the grouping of individuals within their own populations and the clustering of populations within species. Individuals of A. charidemi, A. valentinum and A. subbaeticum, from subsection Valentina, made up a discrete group, whereas the samples belonging to subsection Sempervirentia (A. petegasii, A. sempervirens, A.microphyllum, A. pulverulentum) clustered together. RAPD data are entirely congruent with the subsection classification scheme proposed by Fernández Casas (1997) in section Sempervirentia. However, A. subbaeticum, treated as a synonym of A. valentinum by Fernández-Casas (1997), showed an unique RAPD profile characterized by the highest number of fixed species-specific markers found in section Sempervirentia. Thus, although A. valentinum appeared the most closely related species to A. subbaeticum, molecular data suggested that this species merits taxonomic distinction.

Molecular taxonomy and genetic diversity of Moricandia moricandioides subsp. pseudofoetida compared to wild relatives

Abstract Moricandia moricandioides subsp. pseudofoetida is a taxon endemic to the southeast of the Iberian Peninsula, of which only one population is known. In this study, we used Inter Simple Sequence Repeat molecular markers to compare the taxons genetic diversity with that of populations with similar ecological characteristics belonging to Iberian endemic species of the genus Moricandia (M. moricandioides subsp. moricandioides and Moricandia foetida) and to the widely distributed Moricandia arvensis, in the context of the southeast of the Iberian Peninsula. The results indicated that M. moricandioides subsp. pseudofoetida has genetic diversity values similar to the two other endemic taxa, while M. arvensis has higher diversity values. We established a hypothesis concerning the origin of M. moricandioides subsp. pseudofoetida, since our results suggested that this taxon arose by reproductive isolation rather than hybridization between M. foetida and M. moricandioides. Our results might serve as a starting point to obtain a clear phylogenetic pattern for the genus. Finally, we proposed measures for the conservation of this rare taxon and recommendations for the collection of siliques to establish a seed bank.

Taxonomy and Phylogeny of Andina (Pottiaceae, Bryophyta): a New Moss Genus from the Tropical Andes

Abstract Andina, a new genus of Pottiaceae, is described with seven species from the Andes. Andina elata and A. granulosa are transferred from Pseudocrossidium, A. coquimbensis, A. oedocostata, and A. pruinosa from Didymodon, and A. churchilliana and A. limensis are newly described. The genus can be distinguished from all other Pottiaceae by a combination of characters: absence of a stem hyalodermis, axillary hairs with brownish basal cells, cucullate leaf apices, strongly recurved to revolute leaves with margins infolded at the apex, red to orange coloration of the lamina when exposed to potassium hydroxide, ventral costal outgrowths differentiated as a pad of bulging and papillose cells, filaments, or lamellae, and upper laminal cells usually bulging on both surfaces. Maximum parsimony and Bayesian analyses of plastid DNA sequences (trnL-trnF and trnG) were undertaken to estimate the phylogenetic position of the new genus. The molecular data suggest a close relationship of Andina to the genera Gertrudiella and Didymodon with which it shares a common ancestor.

Helianthemum motae (Cistaceae), a New Species from Southeastern Spain

Helianthemum motae Sánchez-Gómez, J.F. Jiménez & J.B. Vera (Cistaceae) is described as a new species from southeastern Spain. It belongs to the section Lavandulaceum and appears to be close to H. syriacum. The diagnostic characters, a phylogenetic study as well as a full description, a dichotomic key, and illustrations are provided. Both macromorphological and micromorphological characters are discussed and compared with the morphologically related species. The conservational status of H. motae is discussed.

Licmophora colosalis sp. nov. (Licmophoraceae, Bacillariophyta), a large epiphytic diatom from coastal waters

Abstract: The characteristic wedge-shape and large size of some diatom species in the genus Licmophora can make them seem relatively easy to identify. However, this is not always the case, as many specific diagnoses are based solely on light microscopy, type material is not available and species may be difficult to distinguish from each other. This study provides the description and phylogenetic position of Licmophora colosalis sp. nov., which has large cells and extremely long dichotomously branched stalks that form macroscopic arborescent colonies. Material for this study was collected from a hypersaline Mediterranean lagoon but this species has also been reported from Florida and the Red Sea. It was studied using scanning electron microscopy and sequencing of the nuclear small subunit rDNA (SSU) and the chloroplast marker rbcL. Its colonies and cell morphometry are compared with three morphologically similar taxa: Licmophora remulus, Licmophora gigantea and Licmophora grandis.

Genetic diversity of Viola cazorlensis Gand., an endemic species of Mediterranean dolomitic habitats: implications for conservation

Viola cazorlensis is a South Iberian endemic (Spain), which is protected at European level, nationally as well as regionally, and considered vulnerable (VU) in accordance with IUCN criteria. This study has researched the genetic variability of seven representatives of V. cazorlensis populations, both inter- and intra-populationally, through the use of ISSR molecular markers and the sequencing of plastidial intergenic spacers. Results obtained from the ISSR markers indicate that these V. cazorlensis populations are not genetically impoverished, and that no clear genetic structure pattern exists. From the sequencing of plastidial intergenic spacers, the presence of different haplotypes has been observed, which becomes more evident as geographic distance among populations increases. Furthermore, there is a certain gene flow among them, more effective at a nuclear level, which could be mediated by Macroglossum stellatarum pollinator. The results obtained lead to the discussion of a series of conservation measures.

Genetic diversity of Narcissus tortifolius, an endangered endemic species from Southeastern Spain

Abstract In this work, we analyzed inter-simple sequence repeat markers from 10 populations (298 individuals) spanning the whole distribution range of the endemic Narcissus tortifolius. We assessed genetic variation levels and distribution by estimates of genetic diversity, analysis of molecular variance (AMOVA), principal coordinates and Bayesian methods. N. tortifolius showed moderate genetic diversity at intrapopulation level and low genetic differentiation of populations. In general, Almerian populations showed slightly higher levels of genetic diversity than Murcian populations. Our results indicate that habitat fragmentation has not caused genetic depauperation in N. tortifolius but did reveal moderate genetic differentiation. Indeed, principal coordinate analysis and Mantel test revealed a slight tendency to separate populations into two groups (Murcian vs. Almerian). A recent isolation event of populations, together with the perennial nature of this species could be the main reasons for this low to moderate differentiation. Our findings could be used to establish management guidelines for the conservation of this rare species.

Phylogenetic relationships in the genus Hennediella (Pottiaceae, Bryophyta) inferred from nrITS sequence data

The first phylogenetic study of the genus Hennediella using nuclear ITS rDNA for 11 of the 15 species recognized is presented. Maximum parsimony, maximum likelihood, and Bayesian analyses were performed to evaluate the monophyly of the genus and to investigate phylogenetic relationships between the species. The molecular data suggest that the core Hennediella is monophyletic only including Tortula platyphylla, although the affinities of two species (Hennediella heteroloma and H. longipedunculata) are ambiguous. The ITS sequences did not fully resolve the internal relationships of Hennediella while its affinities with Dolotortula, Leptophascum, Sagenotortula, or Tortula remain ambiguous. The present circumscription of Hennediella is provisional until a morphological revision of genus Tortula is completed.

Morphology and molecular phylogeny of Hyalosynedra lanceolata sp. nov. and an extended description of Hyalosynedra (Bacillariophyta)

ABSTRACT The araphid diatom genus Hyalosynedra is a very common component of marine benthic communities, occurring as an epiphyte or colonizing hard substrata, and has a worldwide distribution. The hyaline appearance of the valve and the high striation density, which is indiscernible under a light microscope, makes the identification of most species difficult and very few studies have investigated their morphology, phylogeny or ecology in detail. In an extensive study of diatom communities from the hypersaline Mar Menor coastal lagoon (SE Spain), several new taxa were found. Herein we propose Hyalosynedra lanceolata sp. nov. based on morphological observations (light and electron microscopy) and molecular data (phylogenetic and sequence divergence analyses). The species has distinctive morphological characters (radiate colony, biseriate striation, lanceolate sternum and two long laminar lobed chloroplasts) that are new for the genus and have been included in a proposal to extend the genus description. Our results also show that H. toxoneides does not belong to Hyalosynedra, but appears to be more closely related to Thalassionema and Thalassiothrix. However, further molecular and morphological research is needed to clarify its taxonomic position.